Buffer layer configuration for wideband microstrip patch antenna for underwater applications

Underwater wireless systems require highly efficient underwater antennas to realize high data rate communication. Since most underwater environments are lossy mediums affecting the characteristics of conventional antennas, an antenna contained by a buffer-layer is considered. This paper presents a numerical study on the relationship between the buffer layer characteristics and the antenna performance when operating underwater, by means of 3D-electormagnetic simulation. A wideband microstrip circular patch antenna operating around 500 MHz frequency was used as the base antenna, where it was contained in a buffer layer filled with water with different material parameters. This study proposes the utilization of a buffer layer with dielectric constant value calculated using geometric average among air and the transmission medium. Initial simulation results indicated that the proposed formula produced the best antenna gain and commendable return loss at 500 MHz frequency band.